Your friend and you see a rainbow. Both of you enjoy its seven beautiful colours. But do you wonder if both of you are seeing the same thing?
Is it possible that different people see the exact same thing – differently? Strange as it may sound, scientists say yes. It is quite apparent in the case of colours. People have different perception to colours.
Himba tribe color study
In Namibia there is an aboriginal tribe called as the Himba. According to the BBC, when scientists showed various colours to the Himba tribe, they noticed a strange thing. They cannot classify or distinguish between the colours blue and green. They had the same eyesight if not better than us yet blue and green were not like we see it. This may seem like they have some colour blindness but it was not the case. They could identify various shades of greens better than us. These were many shades of green which modern people can hardly tell the difference. According to Mark Frauenfelder at Boing Boing these were the colours shown to the Himba. How many greens can you see?
Normally a modern man can identify one to three shades maximum. The Himba people could tell that each was a different shade. It was put under an RGB identification tool and each colour was definitely a different green.
Anthropologist Alexandre Surrallés speaks of another interesting study from Peru. Candoshi is a tribe that lives along the bank of the Amazon River. The tribe has around 3,000 people. When Surrallés showed them a colour or shade, he noticed that they called it by the name of a ‘thing’ whose colour resembles it. He worked with them for three years and his fieldwork showed that the Candoshi people do not have words for colours. They describe it from what they see in first hand around them. The Candoshi even do not have words for all the colours of the rainbow. That leads that they do not perceive the colours as we do.
Hundreds of studies lead to show that the perception of colour can be influenced by language, culture and natural surroundings. It is not set the same for all human beings on earth. It can be learned and developed.
Colour is in the eye of the beholder
Scientists assume that all people across all cultures can identify these six basic colours – black, white, red, yellow, blue and green. However studies show some cultures may not. Is colour truly in the eye of the beholder? How do we actually sense colours?
Our eye and brain reacts to light in a complex way. When light falls on the eye, it is analyzed by the nerve cells as wavelengths. Blue has a short wavelength and red has the highest. The colours of the rainbow are arranged from the shortest to the longest as violet, indigo blue, green, yellow, orange, and red. Beyond red is the infrared wavelength which is not visible to the human eye. When we see something, we see that light whose wavelength has been reflected. The photoreceptors in our eye called the cones respond to it.
Researchers believe that although the science is the same for all, the perception of the colour is done by the brain. The brain recognizes the colour as per its memory and learning. That is why we overlook a shade that our brains do not have a prior recognition of. Studies also show that colours can ‘look’ different in different moods. Emotions and memories make us see and react to colours. Thus for each person, a hue can reveal a different meaning and hence affect our perception of that.
One unexplained phenomenon of the perception of the colours by human eye is the tetrachromats. Normally we see colours in three main ranges – red, blue and green. The photoreceptors in our eyes are built that way. But in some people we also see a fourth photoreceptor. These people are called tetrachromats. The tetrachromats can perceive colours far more than us normal humans.
Scientists also found that our language affects the recognition of colours. In fact studies have shown that some cultures have more words for colours. Naturally the children of these cultures can recognize and identify more colours. Children who are exposed to colouring pencils and crayons at an early age have a better colour recognition skill. Crayon makers introduce and label different colours and pencils to increase their sales as kids pick up these new colours well. This shows how much our conditioning and growing up affects the way we see the world. It also means no two people can be said to see the world in the same way.
Related: What is so weird about our eyes?
When did blue become a colour ?
There is a new controversial study that says that the colour blue has been historically absent in ancient cultures. Cave paintings lack any blue hues. Scientists have studied hundreds of ancient texts around the world and say that the blue colour has not been mentioned. They say that people in the earlier times could not perceive blue as a different colour.
The blue had been first mentioned during the Egyptian civilization about 6,000 years ago. The lapis lazuli stones from Afghanistan were brought to Egypt to create the blue hue. The blue dye was used but only among the royals. Gradually the shade was picked up by the Persians and Romans. Since then, the blue colour has evolved and spread as a popular hue. New shades of blue are even being discovered today.
Professor Mas Subramanian of Oregon State University developed the newest blue shade in 2009. He created this new blue by accident while he was experimenting for electronics. While doing an experiment with heated Yttrium oxide, Indium oxide and Manganese oxide, he discovered a vibrant blue mixture. He casually called this new pigment ‘YInMn blue’ after its ingredients. However, this new shade looked attractive to crayon making firm Crayola. The company has decided to introduce this pigment as a new crayon for children. They say that this new blue is quite stable and also non toxic, making it a good option for colouring crayons.
Could it be that there are still many colours around us that we cannot see and recognize? Perhaps as we evolve, we can see those one day.
How Language Changes The Way We See Color
Here is a video by Business Insider with colour expert Gavin Evans. Evans speaks of how the colour blue may have been historically absent. He also speaks about the Himba tribe of Namibia and how the people perceive colours in their language.
Credits: boingboing.net, sapiens.org/language/color-perception, dunnedwards.com/colors/specs/posts/the-history-and-science-behind-the-color-blue